Understanding Atoms and Isotopes

What is the approximate radius of an atom?

Which part of the atom contains most of its mass?

• Electrons

• Nucleus

• Energy levels

• Protons

What happens to electron arrangements when electromagnetic radiation is absorbed?

• Electrons move closer to the nucleus

• Electrons move further from the nucleus

• Electrons remain in the same position

• Electrons are ejected from the atom

What is the atomic number of an element?

• The total number of protons and neutrons

• The number of electrons

• The number of protons

• The number of neutrons

Which model of the atom suggested that it was a ball of positive charge with negative electrons embedded in it?

• Nuclear model

• Plum pudding model

• Bohr model

• Rutherford model

What type of radiation consists of two protons and two neutrons?

• Beta particle

• Gamma ray

• Alpha particle

• Neutron

What is the unit of measurement for radioactive activity?

• Hertz (Hz)

• Joule (J)

• Becquerel (Bq)

• Coulomb (C)

Which scientist's work provided evidence for the existence of neutrons?

• Niels Bohr

• Ernest Rutherford

• James Chadwick

• J.J. Thomson

What is the charge of an alpha particle?

• Neutral

• Positive

• Negative

• Variable

Which type of radiation is the most penetrating?

• Neutron radiation

• Beta radiation

• Alpha radiation

• Gamma radiation